The invention relates to wax-like polymerizable materials. The invention provides wax-like polymerizable dental materials for making dentures. xe2x80x9cWax-likexe2x80x9d as used herein refers to material which is flowable (fluid) above 40xc2x0 C., and becomes dimensionally stable (solidifies: i.e. is nonfluid) at least at and below 23xc2x0 C., in order of decreasing preference, within 5, 2, 1, 0.5 or 0.3 minutes.
A common prior art method of making dentures begins with an impression of a patient""s mouth to form a plaster cast model (or record base). Dental wax is shaped into the form of a denture base on the cast and artificial teeth are positioned into the denture base shaped wax. The denture base shaped wax with the artificial teeth is then positioned in an articulator. The articulated denture base shaped wax with the artificial teeth is positioned in a flask mold. The volume of the flask is filled with hardenable investment material, such as plaster, which fixes the positioning of the teeth. After the investment material hardens, the wax is eliminated by melting, for example by heating the flask in boiling water, leaving the artificial teeth supported by the investment material and forming a denture base shaped mold cavity within the investment material. After a thorough cleansing of the mold cavity, a denture base resin material is introduced into the mold cavity. The denture base material then hardens to form a denture.
Volkel et al in U.S. Pat. No. 6,057,383 (and Canadian Patent Application 2207351), assigned to Ivoclar, disclose wax-like polymerizable material for making entire dental products. The prior art does not disclose a wax-like polymerizable material for forming dentures or other high strength products. The prior art does not disclose a process for making a denture, including positioning artificial teeth in high strength product forming wax-like polymerizable material supported by a base plate; shaping the polymerizable material to support the teeth; and polymerizing the material, whereby a denture is provided, which process does not require the use of conventional wax or positioning artificial teeth in a mold. These limitations of the prior art are overcome by the present invention.
It is an object of the invention to provide a high strength dental polymeric material formed from wax-like polymerizable dental material.
It is an object of the invention to provide a wax-like polymerizable dental material formed by a process comprising blending polymerizable compounds which polymerize to form high strength dental polymeric material.
It is an object of the invention to provide a method comprising forming high strength dental polymeric material from wax-like polymerizable dental material.
It is an object of the invention to provide a process for making a denture, comprising positioning artificial teeth in wax-like polymerizable dental material.
Wax-like polymerizable dental material of the invention is polymerizable to form high strength dental polymeric material. xe2x80x9cHigh strength dental polymeric materialxe2x80x9d as used herein refers to polymeric material having a flexural modulus of at least 250,000 psi and a flexural strength of at least 5,000 psi. Wax-like polymerizable dental material of the invention is wax-like i.e. flowable above 40xc2x0 C., and becomes dimensionally stable (solidifies and is nonfluid) at least at and below 23xc2x0 C. While cooling from above 40xc2x0 C. to 23xc2x0 C. the wax-like polymerizable dental material preferably changes from being flowable to being dimensionally stable within 2 minutes. The wax-like polymerizable dental material is readily polymerized to form high strength dental polymeric material in shapes (or forms) of high strength dental polymeric products. Preferably high strength dental polymeric material has a flexural modulus of at least 300,000 psi and a flexural strength of at least 7,000 psi, and an un-notched impact strength of at least 2 foot-pounds/inch. More preferably high strength dental polymeric material in order of increasing preference has a flexural modulus of at least 350,000, 400,000, 450,000 or 500,000 psi and a flexural strength of at least 12,000, 15,000 and 16,000 psi, and an un-notched impact strength of at least 3.0, 3.5, 4.0 or 6.0 foot-pounds/inch. High strength dental polymeric material is preferably formed into dental products including full dentures, partial dentures, denture relines, night guards, crowns and bridges by polymerization of wax-like polymerizable dental material.
The invention provides a method of forming a high strength dental polymeric material, comprising polymerizing a wax-like polymerizable dental material. The invention provides a denture comprising: at least one artificial tooth and high strength dental polymeric material formed from the wax-like polymerizable dental material.